Use of colorless, intensely fluorinated ammonium and iminium compounds as charge control agents for electrophotographic recording processes

ABSTRACT

The use of intensely fluorinated ammonium compounds of the general formula (I) ##STR1## in which R 1  to R 4  denote hydrogen atoms or organic radicals, at least one of the radicals R 1  to R 4  denoting a straight-chain or branched fluorine-containing alkyl radical or fluorine-containing alkenyl radical which contains 1 to 69 carbon atoms and 3 to 66 fluorine atoms and which may be substituted, and at most three of the radicals R 1  to R 4  are, independently of one another, hydrogen atoms, straight-chain or branched alkyl radicals or alkenyl radicals containing 1 to 30 carbon atoms, aryl radicals or aralkyl radicals, and X -  denotes an organic or inorganic anion, and of intensely fluorinated iminium compounds of the general formula (II) ##STR2## in which R 9  to R 12  denote hydrogen atoms or organic radicals, at least one of the radicals R 9  to R 12  denoting a straight-chain or branched fluorine-containing alkyl radical or fluorine-containing alkenyl radical which contains 1 to 69 carbon atoms and 3 to 66 fluorine atoms and which may be substituted, and at most three of the radicals R 9  to R 12  denote, independently of one another, hydrogen, straight-chain or branched alkyl radicals or alkenyl radicals containing 1 to 30 carbon atoms, aryl or aralkyl radicals and Y -  is an organic or inorganic anion, as colorless charge control agents having positive or negative control effect in toners and developers for electrophotographic recording processes.

DESCRIPTION

The present invention relates to the use of intensely fluorinatedammonium and iminium compounds as colorless charge control agents foruse in toners and developers for electrophotographic recordingprocesses. As a result of the selective introduction offluorine-containing organic radicals, the compounds according to theinvention have particularly beneficial charge control properties.

In electrophotographic recording processes, a "latent charge image" isproduced on a photoconductor. This is done, for example, by charging upa photoconductor by means of a corona discharge and then exposing theelectrostatically charged-up surface of the photoconductor to an image,in which process the exposure brings about the charge drainage to theearthed substrate at the exposed points. The "latent charge image"produced in this way is then developed by applying a toner. In asubsequent step, the toner is transferred from the photoconductor to,for example, paper, textiles, films or plastic and fixed thereon, forexample, by pressure, radiation, heat or exposure to solvent. Thephotoconductor used is then cleaned and is available for a new recordingcycle.

Numerous patents describe the optimization of toners, in whichconnection, inter alia, the effect of the toner binder (variation ofresin/resin components or wax/wax components), the effect of controlagents or other additives or the effect of carriers (in the case oftwo-component developers) and magnetic pigments (in the case ofsingle-component developers) were investigated (U.S. Pat. No.2,221,776).

A measure of the quality of a toner is its specific chargeability Q/M(charge per unit mass). In addition to the sign and magnitude of theelectrostatic charging, the rapid achievement of the desired magnitudeof charging and the constancy of this charge throughout a prolongedactivation period are, in particular, a decisive quality criterion. Inpractice, this is of central importance inasmuch as the toner may beexposed to a considerable activation time in the developer mixturebefore it is transferred to the photoconductor, since it sometimesremains in the developer mixture for a period in which up to severalthousand copies are produced. In addition, the insensitivity of thetoner to climatic effects such as temperature and atmospheric humidityis a further important criterion of suitability.

Both positively and negatively chargeable toners are used in copiers andlaser printers, depending on the type of process and type of equipment.

In order to obtain electrophotographic toners or developers havingeither positive or negative triboelectric chargeability, so-calledcharge control agents (also called charge regulation agents) are oftenadded. In this connection, in addition to the sign of the charge controlthe extent of the control effect is of importance since a highereffectiveness makes it possible to use a smaller amount.

Since, as a rule, toner binders alone produce a considerable change inthe charging depending on the activation time, the object of a chargecontrol agent is, on the one hand, to establish the sign and magnitudeof the toner charging and, on the other, to counteract the chargingdrift of the toner binder and to ensure constancy of the toner charging.Charge control agents which are incapable of preventing the toner ordeveloper exhibiting a high charging drift (aging) during a prolongedperiod of use and which may even result in the toner or developerundergoing a charge reversal are therefore unsuitable for practical use.

Full-color copiers and full-color laser printers employ the principle oftrichromatism which makes an exact hue matching of the three primarycolors (yellow pigment, cyan pigment and magenta pigment) necessary. Theslightest displacements in the hue of even only one of the three primarycolors requires of necessity a displacement in the hue of the two othercolors in order to be able to produce full-color copies or full-colorprints true to the original even under those circumstances. Owing to theprecise matching of the coloristics of the individual pigments to oneanother, necessary in color toners, charge control agents havingabsolutely no inherent color are very particularly important.

In color toners, the three toners yellow, cyan and magenta have to beprecisely matched to one another not only in relation to the preciselydefined color requirements, but also in relation to their triboelectricproperties. This triboelectric matching is necessary because, in thecase of a full-color print or in the case of a full-color copy, thethree color toners (or four color toners if black is included) have tobe transferred consecutively in the same equipment.

It is known that color pigments may sometimes have a very intense effecton the triboelectric charging of toners (H. T. Macholdt, and A. Sieber,Dyes & Pigments 9 (1988), 119-27; U.S. Pat. No. 4,057,426;EP-A-247,576). Owing to the different triboelectric effects of colorpigments and the very marked effects on the toner chargeabilitysometimes resulting therefrom, it is not possible to add them as thesole colorant to a toner base formulation once it has been produced. Onthe contrary, it may be necessary to produce for each colorant aparticular formulation for which, for example, the type and amount ofthe charge control agent needed are specifically designed. Thisprocedure is correspondingly elaborate and, in the case of color tonersfor process color (trichromatism), adds still further to thedifficulties already described. Highly effective, colorless chargecontrol agents which are capable of compensating for the differingtriboelectric behavior of different pigments and imparting the requiredcharging to the toner are therefore required. In this manner,triboelectrically very different pigments can be used in the differenttoners necessary (yellow, cyan, magenta) on the basis of a toner baseformulation containing one and the same charge control agent once theformulation has been produced.

Colorless charge control agents for electrophotographic toners anddevelopers which have been described are ammonium compounds (forexample, EP-A-203,532, EP-A-242,420, U.S. Pat. No. 4,683,188, U.S. Pat.No. 4,684,596) and phosphonium compounds (for example, U.S. Pat. No.3,893,935, U.S. Pat. No. 4,496,643), metal complexes and organometalliccompounds (for example, U.S. Pat. No. 4,656,112, DE-A-3,144,017,JP-A-61-236,557, JP-A-62-127,754, JP-A-62-287,262), and also a number ofother compounds (for example, EP-A-216,295).

Positive colorless charge control agents essentially include quaternaryammonium compounds and phosphonium compounds and also some organotin andorganoantimony compounds. However, the colorless charge control agentsknown hitherto have a number of disadvantages which severely limit theiruse in practice or in some cases even make it impossible. Thus, thequaternary ammonium compounds, which are suitable per se, are difficultto disperse and may result in non-uniform charging of the toner, and thetoner charge they produce is not stable over a prolonged activationtime, in particular at high temperature and atmospheric humidity(EP-A-242,420). Furthermore, such compounds may be sensitive to light ormechanical effects (EP-A-203,532, U.S. Pat. No. 4,683,188) and thermallylabile, and may yield decomposition products which may bedisadvantageous for the triboelectric charging of the toner (U.S. Pat.No. 4,684,596). In addition, they often exhibit wax-like behavior, andin some cases solubility in water and low effectiveness as chargecontrol agents (see Comparison Examples).

Phosphonium salts are less effective than ammonium salts as chargecontrol agents (U.S. Pat. No. 4,496,643) and may present toxicologicalproblems. Thus, for example, tetran-butylphosphonium bromide (U.S. Pat.No. 3,893,935), which is known as a charge control agent, is a strongskin and mucous membrane irritant.

Organotin borates as described in EP-A-216,295, and also organotincompounds (JP-A-62-287,262) and organoantimony compounds(JP-A-61-236,557) present problems owing to their heavy-metal content.

The known negative colorless charge control agents are almostexclusively heavy-metal compounds, namely chromium complexes, ironcomplexes, cobalt complexes (DE-A-3,144,017) and zinc complexes (U.S.Pat. No. 4,656,112, JP-A-62-127,754). In addition to the heavy-metalproblems, it is also a disadvantage that some of these compounds are notreally colorless and consequently find only limited use in color toners.

In addition to incorporation in the toner resin, charge control agentsare also used for coating carriers. In this case, the same compoundclasses are used as for incorporation in toner resins, for exampleammonium compounds (JP-A-61-258,270) and phosphonium compounds(JP-A-61-260,258), and also heavy-metal complexes and heavy-metalorganic compounds (JP-A-61-147,261, JP-A-61-259,267).

Basically, it may be stated that colorless charge control agents are inprinciple known both for positive toners and for negative toners, butare only of limited suitability for use in practice, or are unusable, orstill require substantial improvement.

The object of the present invention was therefore to find improvedcharge control agents which are distinguished by the absolute absence ofan inherent color, have a higher effectiveness, are suitable, inparticular, for use in color toners, and adjust the electrostaticcharging of toners and developers rapidly and as a function ofconcentration. Furthermore, they should keep the electrostatic chargingconstant over a prolonged activation period (no aging), functionsatisfactorily, especially at high atmospheric humidity, and becompatible with common toner resins and readily dispersible.

Surprisingly, it has now emerged that ammonium compounds and iminiumcompounds which are intensely fluorinated have particularly beneficialproperties as colorless charge control agents for electrophotographictoners and developers. Because of their colorlessness, higheffectiveness, good compatibility and dispersibility in common tonerresins and chemical inertness, the compounds are suitable, inparticular, for use in color toners or color developers for full-colorcopiers based on the principle of trichromatism (subtractive colormixing), and even for colored toners or developers in general and forblack toners or developers. Particularly surprising is the fact thatsubstances of one and the same compound class, depending on the chemicalmodification, are suitable either as positive or as negative chargecontrol agents (see Application Examples 2 and 4). Furthermore, thecompounds are also suitable for coating carriers.

A considerable technical advantage of these readily dispersiblecompounds is that substances of the same compound class can be usedeither as positive or as negative control agents. Consequently, problemswith incorporation into the toner binder and compatibility with thetoner binder after producing a toner base formulation are minimized.Thus, positive toners and also negative toners can be produced on thebasis of a fixed toner base formulation (composed of toner binder,pigment, flow promoter and other constituents) by incorporating thedesired control agent.

The synthesis of fluorinated quaternary ammonium compounds and iminiumcompounds is known and is described in U.S. Pat. No. 3,535,381, FR-PS2,153,489, DE-A-1,922,277, DE-A-2,244,297 and also DE-A-3,306,933. Suchcompounds are used, for example, as surface-active substances,emulsifiers and flow accelerators as described in DE-A-2,244,297, DE-PS2,749,330, DE-A-3,347,378 and BE-PS 788,335. Completely novel, however,is their use as charge control agents in electrophotographic toners anddevelopers.

The present invention relates to the use of intensely fluorinatedammonium compounds of the general formula (I) ##STR3## in which R₁ to R₄denote hydrogen atoms or organic radicals, at least one of the radicalsR₁ to R₄ denoting a straight-chain or branched fluorine-containing alkylradical or fluorine-containing alkenyl radical which contains 1 to 69carbon atoms and 3 to 66 fluorine atoms and which may contain hydroxyland/or chloromethyl and/or carboxylic acid amide and/or sulfonic acidamide and/or urethane and/or amino and/or R₅ -O-R₆ and/or ##STR4##groups in which R₅, R₆, R₇ and R₈ are (C₁ -C₃₀)alkyl radicals and atmost three of the radicals R₁ to R₄ are, independently of one another,hydrogen atoms, straight-chain or branched alkyl radicals or alkenylradicals containing 1 to 30 carbon atoms, aryl radicals such as, forexample, phenyl radicals or naphthyl radicals, or aralkyl radicals suchas, for example, benzyl radicals, it being possible for the arylradicals and aralkyl radicals to be substituted on the aromatic nucleusby (C₁ -C₃₀) alkyl, (C₁ -C₃₀)alkoxy or hydroxyl groups or halogen atomssuch as, for example, fluorine, chlorine, bromine or iodine atoms, andfor two of the radicals R₁ to R₄ to join together to form a mono- orpolynuclear ring system containing 4 to 12 carbon atoms which may beinterrupted by 1 to 4 hetero atoms such as, for example, nitrogen,oxygen or sulfur atoms and may contain 0 to 6 double bonds and also besubstituted by fluorine, chlorine, bromine or iodine atoms, (C₁ -C₆)alkyl, (C₁ -C₆) alkoxy, nitro or amino groups, and X. denotes an organicor inorganic anion, it being possible for the radicals R₁ to R₄ to besubstituted by a COO⁻ or SO₃ ⁻ group and X⁻ ceasing in this case to beapplicable, and of intensely fluorinated iminium compounds of thegeneral formula (II) ##STR5## in which R₉ to R₁₂ denote hydrogen atomsor organic radicals, at least one of the radicals R₉ to R₁₂ denoting astraight-chain or branched fluorine-containing alkyl radical orfluorine-containing alkenyl radical which contains 1 to 69 carbon atomsand 3 to 66 fluorine atoms and which may contain hydroxyl and/orchloromethyl and/or carboxylic acid amide and/or sulfonic acid amideand/or urethane and/or amino and/or R₅ --O--R₆ and/or R₇ C(O)-O-R₈groups, in which R₅, R₆, R₇ and R₈ have the abovementioned meanings, andat most three of the radicals R₉ to R₁₂ denote, independently of oneanother, hydrogen atoms, straight-chain or branched alkyl radicals oralkenyl radicals containing 1 to 30 carbon atoms, aryl radicals such as,for example, phenyl radicals or naphthyl radicals, aralkyl radicals suchas, for example, benzyl radicals, it being possible for the arylradicals or aralkyl radicals to be substituted on the aromatic nucleusby (C₁ -C₃₀) alkyl, (C₁ -C₃₀) alkoxy, hydroxyl groups or halogen atoms,and for two of the radicals R₉ to R₁₂ to join together to form a mono-or polynuclear ring system containing 4 to 17 carbon atoms which may beinterrupted by 1 to 4 heteroatoms such as, for example, nitrogen, oxygenor sulfur atoms and may contain 2 to 9 double bonds and also besubstituted by fluorine, chlorine, bromine or iodine atoms, a (C₁ -C₆)alkyl, (C₁ -C₆) alkoxy, nitro or amino group (in this case R₁₂ becomesone of the abovementioned radicals on the ring), and Y⁻ is an organic orinorganic anion, it being possible for the radicals R₉ to R₁₂ to besubstituted by a COO⁻ or SO₃ ⁻ group and Y⁻ ceasing in this case to beapplicable, as colorless charge control agents having positive ornegative regulation effect in toners and developers forelectrophotographic recording processes.

As organic or inorganic anion, X⁻ or Y⁻ may, for example, be Hal⁻ suchas, for example, Cl⁻, Br⁻ or I⁻, and also PF₆ ⁻, sulfate, phosphate,cyanate, thiocyanate, BF₄ ⁻, B(aryl)₄ ⁻ such as, for example,tetraphenyl borate, p-chlorotetraphenyl borate, p-methyltetraphenylborate, tetranaphthyl borate, and also phenolate, nitrophenolate, zinctetracyanate, zinc tetrathiocyanate, CH₃ OSO₃, saturated or unsaturatedaliphatic or aromatic carboxylate or sulfonate such as, for example,acetate, lactate, benzoate, salicylate, 2-hydroxy-3-naphthoate,2-hydroxy-6-naphthoate, ethyl sulfonate, phenyl sulfonate, and alsoperfluorinated saturated or unsaturated aliphatic or aromaticcarboxylate or sulfonate such as, for example, perfluoroacetate,perfluoroalkyl benzoate, perfluoroethyl sulfonate orperfluoroalkylbenzene sulfonate.

The ammonium compounds and iminium compounds of the abovementionedgeneral formula (I) or (II) respectively may be used on their own or incombination in toners or developers which are used forelectrophotographic copying or reproduction of masters and also forprinting electronically, optically or magnetically stored information orin color proofing. In addition, these compounds can be used for coatingcarriers and in powders and paints for surface coating, in particular inelectrokinetically sprayed powder coatings, as charge improving agents.

Particularly suitable are compounds of the said general formula (I) inwhich at least one of the radicals R₁ to R₄ denotes a straight-chainfluorine-containing alkenyl radical which contains 4 to 14 carbon atomsor a straight-chain or branched fluorine-containing alkyl radical whichcontains 13 to 69 carbon atoms and which may contain hydroxyl and/orchloromethyl and/or carboxylic acid amide and/or urethane and/or aminoand/or R₅ --O--R₆ groups in which R₅ and R₆ are (C₁ -C₃₀) alkylradicals, and at most three of the radicals R₁ to R₄ are, independentlyof one another, hydrogen atoms, straight-chain or branched alkylradicals containing 1 to 18 carbon atoms, and X. is an organic orinorganic anion, it being possible for the radicals R₁ to R₄ to besubstituted by a COO⁻ or SO₃ ⁻ group and X⁻ in this case ceasing to beapplicable.

Furthermore, compounds of the said general formula (I) are particularlysuitable in which two of the radicals R₁ to R₄ can join together to forma mono- or polynuclear ring system containing 4 to 10 carbon atoms whichmay be interrupted by 1 to 4 hetero atoms such as, for example,nitrogen, oxygen or sulfur atoms and may contain 0 to 4 double bonds andalso be substituted by fluorine, chlorine, bromine or iodine atoms, a(C₁ -C₆) alkyl, (C₁ -C₆) alkoxy, nitro or amino group, and at least oneof the radicals R₁ to R₄ denotes a straight-chain fluorine-containingalkenyl radical which contains 4 to 14 carbon atoms or a straight-chainor branched fluorine-containing alkyl radical which contains 13 to 69carbons atoms and which may contain hydroxyl and/or chloromethyl and/orcarboxylic acid amide and/or urethane and/or amino and/or R₅ --O--R₆groups in which R₅ and R₆ are (C₁ -C₃₀) alkyl radicals, and at most oneof the radicals R₁ to R₄ denotes a hydrogen atom, a straight-chain orbranched alkyl radical containing 1 to 18 carbon atoms, and X⁻ denotesan organic or inorganic anion, it being possible for the radicals R₁ toR₄ to be substituted by a COO⁻ or SO₃ ⁻ group and X⁻ in this caseceasing to be applicable.

Furthermore, compounds of the abovementioned general formula (II) areparticularly suitable in which at least one of the radicals R₉ to R₁₂denotes a straight-chain fluorine-containing alkenyl radical whichcontains 4 to 14 carbon atoms or a straight-chain or branchedfluorine-containing alkyl radical which contains 13 to 69 carbon atomsand which may contain hydroxyl and/or chloromethyl and/or carboxylicacid amide and/or urethane and/or amino and/or R₅ --O--R₆ groups inwhich R₅ and R₆ are (C₁ -C₃₀) alkyl radicals, and at most three of theradicals R₉ to R₁₂ denote, independently of one another, hydrogen atoms,straight-chain or branched alkyl radicals containing 1 to 18 carbonatoms, and Y⁻ denotes an organic or inorganic anion, it being possiblefor the radicals R₉ and R₁₂ to be substituted by a COO⁻ or SO₃ ⁻ groupand Y⁻ ceasing in this case to be applicable.

Furthermore, compounds of the abovementioned general formula (II) inwhich two of the radicals R₉ to R₁₂ can join together to form a mono- orpolynuclear ring system containing 4 to 10 carbon atoms which may beinterrupted by 1 to 4 hetero atoms such as, for example, nitrogen,oxygen or sulfur atoms and may contain 2 to 5 double bonds and also besubstituted by fluorine, chlorine, bromine or iodine atoms, a (C₁ -C₆)alkyl, (C₁ -C₆) alkoxy, nitro or amino group (in that case, R₁₂ becomesone of the abovementioned substituents on the ring), and one of theradicals R₉ to R₁₂ denotes a straight-chain fluorine-containing alkenylradical which contains 4 to 14 carbon atoms or a straight-chain orbranched fluorine-containing alkyl radical which contains 13 to 69carbon atoms and which may contain hydroxyl and/or chloromethyl and/orcarboxylic acid amide and/or urethane and/or amino and/or R₅ --O--R₆groups in which R₅ and R₆ are (C₁ -C₃₀) alkyl radicals, and Y⁻ is anorganic or inorganic anion, it being possible for the radicals R₉ to R₁₂to be substituted by a COO⁻ or SO₃ ⁻ group and Y⁻ ceasing in this caseto be applicable.

Quite particularly suitable are compounds of the abovementioned generalformula (I) in which at most three of the radicals R₁ to R₄ denote,independently of one another, a methyl, ethyl, stearyl, 2-hydroxyethylor --CH₂ --CH₂ --SO₃ ⁻ group (X⁻ ceases in the latter case to beapplicable) and at least one of the radicals R₁ to R₄ denotes one of thegroupings

    Rf--CF═CH--CH.sub.2 --(Rf═C.sub.5 F.sub.11 --C.sub.11 F.sub.23)

and ##STR6## (Rf=C₈ F₁₇ --C₁₆ F₃₃), it being possible for two of theradicals R₁ to R₄ to join together to form a pyrroline, pyrrolidine,piperidine, morpholine or indoline ring, and X⁻ being BF₄ ⁻, Hal⁻, forexample Cl⁻, Br⁻ or I⁻, and also CH₃ --O--SO₃ ⁻, B(aryl)₄ ⁻ such as, forexample, tetraphenyl borate, p-chlorotetraphenyl borate,p-methyltetraphenyl borate or tetranaphthyl borate.

Of the compounds of the said general formula (II) those are quiteparticularly suitable in which at least one of the radicals R₉ to R₁₂ isa fluorine-containing alkyl radical which contains 1 to 14 carbon atomsand at most three of the radicals R₉ to R₁₂ are, independently of oneanother, methyl, ethyl, stearyl, 2-hydroxyethyl or --CH₂ --CH₃ --O--SO₃⁻ groups (Y⁻ ceasing in the latter case to be applicable), it beingpossible for two of the radicals R₉ to R₁₂ to join together to form apyridine, pyrazine or quinoline ring, and R₁₂ then being a fluorine,chlorine, bromine or iodine atomm or a (C₁ -C₆) alkyl, (C₁ -C₆) alkoxy,nitro or amino group on the ring system, and X⁻ being BF₄ ⁻, Hal⁻ suchas, for example, Cl⁻, Br⁻ or I⁻, and also CH₃ --O--SO₃ ⁻, B(aryl)₄ ⁻such as, for example, tetraphenyl borate, chloroetetraphenyl borate,p-methyltetraphenyl borate or tetranaphthyl borate.

As individual compounds or compound mixtures of the said generalformulae (I) and (II) mention may be made, for example, of thefollowing: ##STR7##

Thus, for example, a toner containing 0.5 to 1.0 percent by weight ofcompound (1) exhibits a charging of -4.0 or -21.7 μC/g after 10 minutesand of -16.6 or -21.6 μC/g after 24 hours of activation time (seeApplication Examples 1 and 2 of the Application Examples below).

A toner containing 2.5 percent by weight of the compound (2) has achargeability of +6.0 μC/g after 10 minutes and of +44 6 μC/g after 24hours of activation time (Application Example 3).

A toner containing 1.0 percent by weight of the compound (3) exhibits achargeability of +13.4 μC/g after 10 minutes and of +13.5 μC/g after 24hours of activation time (Application Example 4).

The compounds of the abovementioned general formulae (I) and (II) mayalso be absorbed on suitable carrier materials such as, for example,silica gel, aluminum oxide, titanium dioxide from suitable media suchas, for example, solutions. Thus, a toner containing 3.0 percent byweight of the compound (5) absorbed on silica gel exhibits a charging of+9.7 μC/g after 10 minutes and of +16.2 μC/g after 24 hours ofactivation time. Compared with the free compound (5), whose action inthe toner collapses at high atmospheric humidity, absorption on silicagel consequently achieves an exceptional effectiveness of the compound(5) even at high atmospheric humidity (Application Example 6).

As already described above, pigments in toners are known to be able toaffect the electrostatic charging of the toner severely. By way ofexamples, mention may be made here of the colorant C.I. Pigment Red 57:1and C.I. Solvent Blue 125. C.I. Pigment Red 57:1 gives a toner a highnegative charging with severe drift towards further increasing negativecharging during prolonged activation time. C.I. Solvent Blue 125produces a high positive charging in a toner which drops to almost zeroduring prolonged activation time as a result of severe drift. It is allthe more surprising that, if 5 percent by weight of the colorant C.I.Pigment Red 57:1 or C.I. Solvent Blue 125 is incorporated along with 1percent by weight of the compound (1) in a toner, the naturaltriboelectric effect of these colorants is fully compensated for by thehigh effectiveness of compound (1) and the required toner charging isestablished (Application Example 7 to 10).

If other ammonium compounds or iminium compounds are used instead of acompound according to the invention, the corresponding toners exhibit amuch lower charging and, in some cases, charge reversal after prolongedactivation time (Comparison Examples 1 and 2).

The compounds according to the invention are, as a rule, homogeneouslyincorporated in the respective carrier material in a concentration ofabout 0.01 to about 10% by weight, preferably about 0.1 to about 5.0% byweight, in a known manner, for example, by kneading in or extruding. Inthis connection, the charge control agents can be added as dried orground powders, dispersions or solutions, press cakes, master batches,as compounds absorbed on suitable carrier materials from aqueous ornon-aqueous solution or in another suitable form. Equally, the compoundsaccording to the invention can also in principle be added even duringthe preparation of the respective toner binders, i.e. in the course ofthe polymerization or polycondensation thereof. Typical toner bindersare, for example, styrene resins, styrene acrylate resins, styrenebutadiene resins, acrylate resins, polyester resins, amide resins, amineresins, ammonium resins, ethylene resins, phenolic resins or epoxyresins, individually or in combination, which may additionally containfurther constituents such as pigments, waxes or flow promoters or whichmay have them added later.

The magnitude of the electrostatic charging of the electrophotographictoners in which the charge control agents claimed according to theinvention have been homogeneously incorporated was measured usingstandard test systems under identical conditions (such as identicaldispersion times, identical particle size distribution, identicalparticle shape) at room temperature and 50% relative atmospherichumidity and also at room temperature at 92% relative atmospherichumidity. For the measurement at 92% relative atmospheric humidity, thetoner concerned was conditioned for 48 hours in a climatic chamber.

The toner in a two-component developer is activated by tumbling with acarrier (three parts by weight of toner to 97 parts by weight ofcarrier) on a roller mixer (150 revolutions per minute). Then theelectrostatic charging is measured using a Q/M test bench (cf. J. H.Dessauer and H. E. Clark, "Xerography and related Processes", FocusPress, N.Y. 1965, page 289).

The particle size is of considerable influence in determining the Q/Mvalue, and for this reason strict attention was paid to uniform particlesize distribution in the toner samples obtained by classifying.

The Examples below serve to explain the invention without restricting itthereto. The parts referred to are parts by weight.

PREPARATION EXAMPLE 1

160 ml of water are added to 40 ml of a 0.5 molar aqueous solution(0.020 mol) of the compound mixture of the formula (5) (molecular weight672) mentioned further above and then 22 ml of a 1.0 M aqueous solutionof sodium tetraphenyl borate (0.022 mol) are added dropwise whilestirring vigorously over a period of 15 to 20 minutes. The solution ismade up to 500 ml with water and heated to 50° C. and the thick whiteprecipitate is filtered off with suction while hot. The product iswashed thoroughly with water and dried at 50° C. in an air-circulationoven.

Yield: 16.9 g (96.0% of theory) of the

compound (1)

Molecular weight: 880.

Melting point: 154-156° C.

Elementary analysis: calc. 4.1% H, 1.6% N, 1.2% B .

exp. 4.1% H, 1.6% N, 1.1% B,

0.05% water .

1H-NMR (in DMSO-d6): 1.20 (triplet, 6 methyl-H),

2.97 (singlet, 3-methyl-H), 3.30.

quartet, 4 ethyl-H), 4.25

(doublet, 2 allyl-H), 6.61

(doublet of triplets,

1 vinyl-H), 7.01 (multiplet, 20

phenyl-H) ppm.

PREPARATION EXAMPLE 2

The preparation of the compound (3) is carried out analogously toPreparation Example (1) using sodium tetrafluoroborate.

Yield: 12.3 g (95.0% of theory) of the

compound (3).

Molecular weight: 648.

Melting point: 202° C.

Elementary analysis: calc. 2.5% H, 2.2% N, 1.7% B

exp. 2.7% H, 2.3% N, 1.8% B,

0.5% water.

1; H NMR (in DMSO-d6): 1.24 (triplet, 6 methyl-H) 3.02

(singlet, 3 methyl-H), 3.37

(quartet, 4 ethyl-H), 4.28

(doublet, 2 allyl-H), 6.63

(doublet of triplets, 1 vinyl

H) ppm.

PREPARATION EXAMPLE 3

The compound (9) is prepared analogously to Preparation Example (1)using the corresponding per fluoroalkylpyridinium iodide and sodiumtetraphenyl borate, and also isopropanol/water (1:1 parts by volume) assolvent.

Yield: 15.2 g (89.7 % of theory) of the

compound (9).

Molecular weight: 845 .

Melting point: 163° C.

Elementary analysis: calc. 55.4% C, 3.5% H, 1.7% N,

1.3% B, 38.2% F

exp. 55.2% C, 3.3% H, 1.6%.N,

1.2% B, 36.8% F, 0.19% water .

1H-NMR (in DMSO-d6): 3.25 (multiplet, 2 methylene-H),

4.97 (triplet, 2 methylene-H),

6.95 (multiplet, 20 phenyl-H),

8.62 (multiplet, 5 pyridyl-H)

ppm.

PREPARATION EXAMPLE 4

20 g of a 50% aqueous solution of the compound (5) are added to 20 g ofsilica gel ("Sipernat 22", manufactured by Degussa) and intimately mixedin a mixer. A fine, dry and readily free-flowing powder containing 25percent by weight of the compound (5) is obtained.

The compounds (2) and also (4) to (8) were prepared analogously to U.S.Pat. No. 3,535,381, FR-PS 2,153,489, DE-A-1,922,277, DE-A-2,244,297,DE-A-3,606,933 and BE-PS 788,335, and the corresponding iodide asstarting compound for the compounds (9) to (11) analogously toDE-A-1,922,277.

APPLICATION EXAMPLE 1

0.5 parts of the compound (1) were homogeneously worked into 99.5 partsof toner binder (Dialec S 309 manufactured by Diamond Shamrock,styrene-methacrylate copolymer 60:40) for 45 minutes by means of akneader manufactured by Werner & Pfleiderer (Stuttgart). Grinding wasthen carried out on the universal laboratory mill 100 LU (manufacturedby Alpine, Augsburg) and classification was then carried out on acentrifugal classifier 100 MZR (manufactured by Alpine). The desiredparticle fraction (4-25 μm) was activated with a carrier of the type 90(Xerographic Carrier manufactured by Plasma Materials Inc.) composed ofmagnetite particles 50 to 200 μm in size coated withstyrene-methacrylate copolymer 90:10. The measurement was carried outusing a standard Q/M test bench (manufactured by Epping GmbH, Neufahrn);a sieve having a mesh size of 25 μm (manufactured by Gebr. Kufferath,Duren) was used to ensure that it was not possible for carrier to beentrained while blowing out the toner. The following Q/M values (μC/g)were measured as a function of the activation time:

    ______________________________________                                        Activation       Q/M (μC/g)                                                time      50%        relative humidity                                                                          92%                                         ______________________________________                                        10    min     -4.0                  -0.6                                      30    min     -6.8                  -4.1                                      2     h       -10.1                 -9.7                                      24    h       -16.6                 -16.5                                     ______________________________________                                    

APPLICATION EXAMPLE 2

The procedure was as described in Application Example 1, with thedifference that 1.0 part of the compound (1) was used in 99 parts oftoner binder.

    ______________________________________                                        Activation       Q/M (μC/g)                                                time      50%        relative humidity                                                                          92%                                         ______________________________________                                        10    min     -21.7                 -16.3                                     30    min     -22.5                 -20.1                                     2     h       -22.9                 -20.9                                     24    h       -21.6                 -19.0                                     ______________________________________                                    

APPLICATION EXAMPLE 3

The procedure was as described in Application Example 1 with thedifference that 2.5 parts of the compound (2) were used in 95 parts oftoner binder.

    ______________________________________                                        Activation       Q/M (μC/g)                                                time      50%        relative humidity                                                                          92%                                         ______________________________________                                        10    min     +6.0                  +3.0                                      30    min     +9.6                  +3.0                                      2     h       +23.6                 +1.3                                      24    h       +44.6                 +18.3                                     ______________________________________                                    

APPLICATION EXAMPLE 4

The procedure was as described in Application Example 1, with thedifference that 1.0 part of the compound (3) was used in 99 parts oftoner binder.

    ______________________________________                                        Activation       Q/M (μC/g)                                                time      50%        relative humidity                                                                          92%                                         ______________________________________                                        10    min     +13.4                 +11.9                                     30    min     +16.9                 +15.7                                     2     h       +17.5                 +16.4                                     24    h       +13.5                 +15.9                                     ______________________________________                                    

APPLICATION EXAMPLE 5

The procedure was as described in Application Example 1, with thedifference that 1.0 part of the compound (4) was used in 99 parts oftoner binder.

    ______________________________________                                        Activation       Q/M (μC/g)                                                time      50%        relative humidity                                                                          92%                                         ______________________________________                                        10    min     +12.8                 +13.0                                     30    min     +15.5                 +14.9                                     2     h       +17.1                 +17.1                                     24    h       +16.8                 +18.3                                     ______________________________________                                    

APPLICATION EXAMPLE 6

The procedure was as described in Application Example 1, with thedifference that 3.0 parts of the compound (5) (in the form of 25 percentby weight of (5) on silica gel ("Sipernat 22", manufactured by Degussa))were used in 91 parts of toner binder and 6 parts of silica gel.

    ______________________________________                                        Activation       Q/M (μC/g)                                                time      50%        relative humidity                                                                          92%                                         ______________________________________                                        10    min     +9.7                  +12.0                                     30    min     +11.9                 +13.2                                     2     h       +14.1                 +13.9                                     24    h       +16.2                 +15.7                                     ______________________________________                                    

APPLICATION EXAMPLE 7

5.0 parts of the colorant C.I. Pigment Red 47:1 were homogeneouslyworked into 95 parts of toner binder as described in Application Example1.

    ______________________________________                                                      Q/M (μC/g)                                                   Activation time                                                                             50% relative humidity                                           ______________________________________                                        10        min      -3.4                                                       30        min     -19.5                                                       2         h       -52.4                                                       24        h       -63.9                                                       ______________________________________                                    

APPLICATION EXAMPLE 8

5.0 parts of the colorant C.I. Solvent Blue 125 were homogeneouslyworked into 95 parts toner binder as described in Application Example 1.

    ______________________________________                                                      Q/M (μC/g)                                                   Activation time                                                                             50% relative humidity                                           ______________________________________                                        10        min     +27.9                                                       30        min     +19.2                                                       2         h       +7.5                                                        24        h       +9.0                                                        ______________________________________                                    

APPLICATION EXAMPLE 9

1.0 parts of the compound (1) and 5.0 parts of C.I. Pigment Red 57:1were homogeneously worked into 95 parts of toner binder as described inApplication Example 1.

    ______________________________________                                        Activation       Q/M (μC/g)                                                time      50%        relative humidity                                                                          92%                                         ______________________________________                                        10    min     -19.6                 -7.3                                      30    min     -22.1                 -12.6                                     2     h       -26.3                 -17.1                                     24    h       -23.3                 -15.0                                     ______________________________________                                    

APPLICATION EXAMPLE 10

1.0 part of the compound (1) and 5.0 parts of C.I. Solvent Blue 125 werehomogeneously worked into 94 parts of toner binder as described inApplication Example 1.

    ______________________________________                                        Activation       Q/M (μC/g)                                                time      50%        relative humidity                                                                          92%                                         ______________________________________                                        10    min     -3.5                  +0.7                                      30    min     -7.7                  -2.0                                      2     h       -8.7                  -5.3                                      24    h       -14.4                 -10.0                                     ______________________________________                                    

APPLICATION EXAMPLE 11

The procedure was as described in Application Example 1, with thedifference that 1.0 part of the compound (9) was homogeneously workedinto 99 parts of toner binder.

    ______________________________________                                        Activation       Q/M (μC/g)                                                time      50%        relative humidity                                                                          92%                                         ______________________________________                                        10    min     -11.8                 +3.7                                      30    min     -11.0                 -5.9                                      2     h       -11.7                 -4.4                                      24    h       -14.7                 -8.0                                      ______________________________________                                    

COMPARISON EXAMPLE 1

The procedure was as described in Application Example 1, with thedifference that 1.0 part of cetylpyridinium chloride was homogeneouslyworked into 99 parts of toner binder.

    ______________________________________                                                      Q/M (μC/g)                                                   Activation time                                                                             50% relative humidity                                           ______________________________________                                        10        min     +12.6                                                       30        min     +7.6                                                        2         h       +0.9                                                        24        h       -9.7                                                        ______________________________________                                    

COMPARISON EXAMPLE 2

The procedure was as described in Application Example 1, with thedifference that 1.0 part of benzyltrimethyl-ammonium chloride was usedin 99 parts of toner binder.

    ______________________________________                                                      Q/M (μC/g)                                                   Activation time                                                                             50% relative humidity                                           ______________________________________                                        10        min     +2.7                                                        30        min     -0.4                                                        2         h       -1.5                                                        24        h       -4.6                                                        ______________________________________                                    

We claim:
 1. A method for effecting in toners and developers a positiveor negative charge control effect (for electrophotographic recordingprocesses) comprising the step of incorporating the compounds of theformula (I) ##STR8## in which R₁ to R₄ denote hydrogen atoms or organicradicals, at least one of the radicals R₁ to R₄ denoting astraight-chain or branched fluorine-containing alkyl radial orfluorine-containing alkenyl radical which contains 1 to 69 carbon atomsand 3 to 66 fluorine atoms and which may contain hydroxyl and/orchloromethyl and/or carboxylic acid amide and/or sulfonic acid amideand/or urethane and/or amino and/or R₅ --O--R₆ and/or R₇ --C(O)--O--R₈groups in which R₅, R₆, R₇ and R₈ and (C₁ -C₃₀) alkyl radicals and atmost three of the radicals R₁ to R₄ are, independently of one another,hydrogen atoms, straight-chain or branched alyl radicals or alkenylradicals containing 1 to 30 carbon atoms, aryl radicals or aralkylradicals which may be substituted by (D₁ -C₃₀) alkyl, (C₁ -C₃₀) alkoxyor hydroxyl groups or halogen atoms, it being possible for two of theradicals R₁ to R₄ to join together to form a mono- or polynuclear ringsystem containing 4 to 12 carbon atoms which may be interrupted by 1 to4 hetro atoms and may contain 0 to 6 double bonds and also besubstituted by fluorine, chlorine, bromine or iodine atoms, (C_(1-C) ₆)alkyl, (C₁ -C₆) alkoxy, nitro or amino groups, and X⁻ denotes an organicor inorganic anion, it being possible for the radicals R₁ to R₄ to besubstituted by a COO⁻ or SO₃ ⁻ group and X⁻ ceasing in this case to beapplicable, and of intensely fluorinated iminium compounds of theformula (II) ##STR9## in which R₉ to R₁₂ denote hydrogen atoms ororganic radicals, at least one of the radicals R₉ to R₁₂ denoting astraight-chain or branched fluorine-containing alkyl radical orfluorine-containing alkenyl radical which contains 1 to 69 carbon atomsand 3 to 66 fluorine atoms and which may contain hydroxyl and/orchloromethyl and/or carboxylic acid amide and/or sulfonic acid amideand/or urethane and/or amino and/or R_(5--O--R) ₆ and/or R₇ C(O)--O--R₈groups, in which R₅,R₆, R₇ and R₈ have the abovementioned meanings, andat most three of the radicals R₉ to R¹² denote, independently of oneanother, hydrogen atoms, straight-chain or branched alkyl radicals oralkenyl radicals containing 1 to 30 carbon atoms, it being possible forthe aryl radials or aralkyl radicals to be substituted on the aromaticnucleus by (C₁ -C₃₀) alkyl, (C₁ -C₃₀) alkoxy, hydroxyl groups or halogenatoms, and for two of the radicals R₉ to R¹² to join together to form amono- or polynuclear ring system containing 4 to 17 carbon atoms whichmay be interrupted by 1 to 4 heteroatoms and may contain 2 to 9 doublebonds and also be substituted by fluorine, chlorine, bromine or iodineatoms, (C₁ -C₆) alkyl, (C₁ -C₆) akloxy, nitro or amino groups, and Y⁻ isan organic or inorganic anion, it being possible for the radicals R₉ toR₁₂ to be substituted by a COO⁻ or SO₃ ⁻ group and Y⁻ in this caseceasing to be applicable, as colorless charge control agents havingpositive or negative charge control effect in toners and developers forelectrophotographic recording processes.
 2. A method as claimed in claim1, wherein, in the formula (I) of claim 1, at least one of the radicalsR₁ to R₄ denotes a straight-chain fluorine-containing alkenyl radicalwhich contains 4 to 14 carbon atoms or a straight-chain or branchedfluorine-containing alkyl radical which contains 13 to 69 carbon atomsand which may contain hydroxyl and/or chloromethyl and/or carboxylicacid amide and/or urethane and/or amino and/or R₅ --O--R₆ groups inwhich R₅ and R₆ are (C₁ -C₃₀) alkyl radicals, and at most three of theradicals R₁ to R₄ are, independently of one another, hydrogen atoms,straight-chain or branched alkyl radicals containing 1 to 18 carbonatoms, and X⁻ is an organic or inorganic anion, it being possible forthe radicals R₁ to R₄ to be substituted by a COO⁻ or SO₃ ⁻ group and X⁻in this case ceasing to be applicable.
 3. A method as claimed in claim1, wherein, in the formula (I) of claim 1, two of the radicals R₁ to R₄form a mono- or polynuclear ring system containing 4 to 10 carbon atomswhich may be interrupted by 1 to 4 hetero atoms and may contain 0 to 4double bonds and also be substituted by fluorine, chlorine, bromine oriodine atoms, (C_(1-C) ₆) alkyl, (C₁ -C₆) alkoxy, nitro or amino groups,and at least one of the radicals R₁ to R₄ denotes a straight-chainfluorine-containing alkenyl radical which contains 4 to 14 carbon atomsor a straight-chain or branched fluorine-containing alkyl radical whichcontains 13 to 69 carbons atoms and which may contain hydroxyl and/orchloromethyl and/or carboxylic acid amide and/or urethane and/or aminoand/or R₅ --O--R₆ groups in which R₅ and R₆ are (C₁ -C₃₀) alkylradicals, and at most one of the radicals R₁ to R₄ denotes a hydrogenatom, a straight-chain or branched alkyl radical containing 1 to 18carbon atoms, and X⁻ denotes an organic or inorganic anion, it beingpossible for the radicals R₁ to R₄ to be substituted by a COO⁻ or SO₃ ⁻group and X⁻ ceasing in this case to be applicable.
 4. A method asclaimed in claim 1, wherein, in the formula (II) of claim 1, at leastone of the radicals R₉ to R₁₂ denotes a straight-chainfluorine-containing alkenyl radical which contains 4 to 14 carbon atomsor a straight-chain or branched fluorine-containing alkyl radical whichcontains 13 to 69 carbon atoms and which may contain hydroxyl and/orchloromethyl and/or carboxylic acid amide and/or urethane and/or aminoand/or R₅ --O--R₆ groups in which R₅ and R₆ are (C₁ -C₃₀)alkyl radicals,and at most three of the radicals R₉ to R₁₂ denote, independently of oneanother, hydrogen atoms, straight-chain or branched alkyl radicalscontaining 1 to 18 carbon atoms, and Y⁻ denotes an organic or inorganicanion, it being possible for the radicals R₉ and R₁₂ to be substitutedby a COO⁻ or SO₃ ⁻ group and Y⁻ ceasing in this case to be applicable.5. A method as claimed in claim 1, wherein, in the formula (II) of claim1, two of the radicals R₉ to R₁₂ form a mono- or polynuclear ring systemcontaining 4 to 10 carbon atoms which may be interrupted by 1 to 4hetero atoms from the series nitrogen, sulfur or oxygen and may contain2 to 5 double bonds and also be substituted by fluorine, chlorine,bromine or iodine atoms, (C₁ -C₆) alkyl, (C₁ -C₆) alkoxy, nitro or aminogroups, and at least one of the radicals R₉ to R₁₂ denotes afluorine-containing alkenyl radical which contains 4 to 14 carbon atomsor a straight-chain or branched fluorine-containing alkyl radical whichcontains 13 to 69 carbon atoms and which may contain hydroxyl and/orchloromethyl and/or carboxylic acid amide and/or urethane and/or aminoand/or R₅ --O--R₆ groups in which R₅ and R₆ are (C₁ -C₃₀) alkylradicals, and Y⁻ is an organic or inorganic anion, it being possible forthe radicals R₉ to R₁₂ to be substituted by a COO⁻ or SO₃ ⁻ group and Y⁻ceasing in this case to be applicable.
 6. A method as claimed in claim 1wherein, in the formulae (I) and (II) of claim 1, X⁻ and Y⁻ denote Cl⁻,Br⁻, I⁻, PF₆ ⁻, sulfate, phosphate, cyanate, thiocyanate, BF₄ ⁻,tetraphenyl borate, p-chlorotetraphenyl borate, p-methyltetraphenylborate, tetranaphthyl borate, phenolate, nitrophenolate, zinctetracyanate, zinc tetrathiocyanate, CH₃ OSO₃ ⁻, saturated orunsaturated aliphatic or aromatic carboxylate or sulfonate,perfluorinated saturated or unsaturated aliphatic or aromaticcarboxylate or sulfonate.
 7. A method as claimed in claim 1, wherein, inthe formula (I) of claim 1, at most three of the radicals R₁ to R₄denote, independently of one another, a methyl, ethyl, stearyl,2-hydroxyethyl or --CH₂ --CH₂ --SO₃ ⁻ group (X⁻ ceases in the lattercase to be applicable) and at least one of the radicals R₁ to R₄ denotesone of the groupings

    Rf--CF═CH--CH.sub.2 --(Rf═C.sub.5 F.sub.11 --C.sub.11 F.sub.23)

and ##STR10## it being possible for two of the radicals R₁ to R₄ to forma pyrroline, pyrrolidine, piperidine, morpholine or indoline ring, and Xbeing BF₄ ⁻, Cl⁻, Br⁻, I⁻ CH₃ --O--SO₃ ⁻, tetraphenyl borate,p-chlorotetraphenyl borate, p-methyltetraphenyl borate or tetranaphthylborate.
 8. A method as claimed in claim 1, wherein, in the formula (II)of claim 1, at least one of the radicals R₉ to R₁₂ is afluorine-containing alkyl radical containing 1 to 14 carbon atoms and atmost three of the radicals R₉ to R₁₂ are, independently of one another,methyl, ethyl, stearyl, 2-hydroxyethyl or --CH₂ --CH₂ --SO₃ ⁻ groups (Y⁻ceasing in the latter case to be applicable), it being possible for twoof the radicals R₉ to R₁₂ to form a pyridine, pyrazine or quinolinering, and R₁₂ then being a fluorine, chlorine, bromine or iodine atom ora (C₁ -C₆)alkyl, (C₁ -C₆)alkoxy, nitro or amino group on the ringsystem, and X⁻ being BF₄ ⁻, Cl⁻, Br⁻, I⁻, CH₃ --O--SO₃ ⁻, tetraphenylborate, chlorotetraphenyl borate, p-methyltetraphenyl borate ortetranaphthyl borate.
 9. A method as claimed in claim 1, wherein thecompounds of the formulae (I) and (II) of claim 1, individually or incombination, are used in a concentration of about 0.01 to about 10% byweight.
 10. A method for preparing toners or developers applicable forthe elecrophotographic copying or reproduction of masters, the printingof electronically, optically or magnetically stored information or thecolor proofing comprising the step of incorporating a compound of theformulae (I) or (II) of claim 1, individually or in combination, intothe toners or developers.
 11. A method for coating carriers applicablefor developers for the electrophotographic copying or reproduction ofmasters, the printing of electronically, optically or magneticallystored information or the color proofing comprising the step of coatingthe carriers with the compounds, individually or in combination, of theformulae (I) or (II) of claim
 1. 12. A method for surface-coating ofobjects of metal, wood, resin, glass, ceramic, concrete, textilematerial, paper or rubber comprising the step of incorporating acompound of the formulae (I) or (II) of claim 1, individually or incombination, as a charge improving (enhancing) agent into powders andpaints, in particular in electrokinetically sprayed powder coatings, forapplying to the surface of the said objects.
 13. A method for effectingin toners and developers a positive or negative charge control effectcomprising the step of incorporating the compounds of the formula (I)##STR11## in which R₁ to R₄ denote hydrogen atoms or organic radicals,at least one of the radicals R₁ to R₄ denoting a straight-chain orbranched fluorine-containing alkyl radicals or fluorine-containingalkenyl radicals which contains 1 to 69 carbon atoms and 3 to 66fluorine atoms and which may contain hydroxyl and/or chloromethyl and/orcarboxylic acid amide and/or sulfonic acid amide and/or urethane and/oramino and/or R₅ --O--R₆ and/or R₇ --C(O)--O--R₈ groups in which R₅, R₆,R₇ and R₈ are (C₁ -C₃₀) alkyl radicals and at most three of the radicalsR₁ to R₄ are, independently of one another, hydrogen atoms,straight-chain or branched alkyl radicals or alkenyl radicals containing1 to 30 carbon atoms, aryl radicals or aralkyl radicals which may besubstituted by (C₁ -C₃₀) alkyl, (C₁ -C₃₀) alkoxy or hydroxyl groups orhalogen atoms, it being possible for two of the radicals R₁ to R₄ tojoin together to form a mono- or polynuclear ring system containing 4 to12 carbon atoms which may be interrupted by 1 to 4 hetero atoms and maycontain 0 to 6 double bonds and also be substituted by fluorine,chlorine, bromine or iodine atoms, (C₁ -C₆) alkyl, (C₁ -C₆) alkoxy,nitro or amino groups, and X⁻ denotes an organic or inorganic anion, itbeing possible for the radicals R₁ to R₄ to be substituted by a COO⁻ orSO₃ ⁻ group and X⁻ ceasing in this case to be applicable, or anintensely fluorinate iminium compound of the formula ##STR12## in whichR₉ to R₁₂ denote hydrogen atoms or organic radicals, at least one of theradicals R₉ to R₁₂ denoting a straight-chain or branchedfluorine-containing alkyl radical or fluorine-containing alkenyl radialwhich contains 1 to 69 carbon atoms and 3 to 66 fluorine atoms and whichmay contain hyroxyl and/or chloromethyl and/or carboxylic acid amideand/or sulfonic acid amide and/or urethane and/or amino and/or R₅--O--R₆ and/or R₇ C(O)--O--R₈ groups, in which R₅, R₆, R₇, and R₈ havethe abovementioned meanings, and at most three of the radicals R₉ to R₁₂denote, independently of one another, hydrogen atoms, straight-chain orbranched alkyl radicals or alkenyl radicals containing 1 to 30 carbonatoms, it being possible for the aryl radicals or aralkyl radicals to besubstituted on the aromatic nucleus by (C₁ -C₃₀) alkyl, (C₁ -C₃₀)alkoxy, hydroxyl groups or halogen atoms, and for two of the radicalsR.sub. 9 to R₁₂ to join together to from a monoor polynuclear ringsystem containing 4 to 17 carbon atoms which may be interrupted by 1 to4 heteroatoms and may contain 2 to 9 double bonds and also besubstituted by fluorine, chlorine, bromine or iodine atoms, (C_(1-C) ₆)alkyl, (C₁ -C₆) alkoxy, nitro or amino groups, and Y⁻ is an organic orinorganic anion, it being possible for the radicals R₉ to R₁₂ to besubstituted by COO⁻ or SO₃ ⁻ group and Y⁻ in this case ceasing to beapplicable, or a combination of a said compound of formula (I) and asaid compound of formula II, as colorless charge control agents havingpositive or negative charge control effect in toners and developers forelectrophotographic recording processes.
 14. A method as claimed inclaim 13, wherein said charge control is present in an amount rangingfrom about 0.01% to about 10% by weight.